Books

Books

Writing Custom Rules for OSSEC: OpenVPN Edition

2 minute read Published:

I wrote some custom rules for OpenVPN on OSSEC yesterday; the full step-by-step with instructions for beginners is included in the latest revision of The Seven Minute Server. But I figure if you’re here, you were searching for this specifically, so here’s the basics: Basic decoder in /var/ossec/etc/local_decoder.xml: <decoder name="openvpn"> <prematch>^\w\w\w\s\w\w\w\s+\d+\s\d\d(:)\d\d(:)\d\d\s\d\d\d\d</prematch> </decoder> I’ll be honest, I’m not a total fan of this approach, but the error logs aren’t formatted consistently, and the only static portion is the date; on the Amazon Linux AMI, it’s the only program that logs in this format (dracut is close, but adds timezone before the year).

Making 8-bit Arcade Games in C

1 minute read Published:

So I bet you thought programming assembly on the web for the Atari 2600 was the ultimate. But check it: You can now use C to develop Z80 CPU-based game platforms like Space Invaders, Galaxian, Sega/Gremlin as well as the Atari vector and Williams platforms. (Atari vector and Williams used the 6502 and 6809 chips, respectively, but Steve tweaked them so that they work with the Z80 compiler.) Type your C source code on the left side of the browser and watch it compile and run in real time on the right side.

First of the 7 Minute Server Series: VPN Servers

3 minute read Published:

I’ve been using a proxy server for awhile, Squid and Privoxy, for fun and also because I saw too many cable and mobile ISPs acting shiftily (why, when I’m connected to Google, do all my connections go to an AT&T server, hmmm?). But the difficulty of setting up a proxy on a cellular connection was annoying — who wants to get Apple Configurator up and running and is that really a feasible solution for a non-technical person who should be able to control their phone’s outbound connections?

Introducing Making Games for the Atari 2600 (and its companion IDE!)

1 minute read Published:

The Atari 2600 was released in 1977, and now there’s finally a book about writing games for it! My partner, Steven Hugg, just released a manual and companion Web-based IDE that’ll teach you about the 6502 CPU, NTSC frames, scanlines, cycle counting, players, missiles, collisions, procedural generation, pseudo-3D, and more. Steve covers the same programming tricks that master programmers used to make classic games. Create your own graphics and sound, and share your games with friends!